Common drive device for date/am/pm display

摘要

A common drive device for date/am/pm display to change transmission ratio of driven mechanism with 24H as a stepping cycle found with the date display in window or indicator hand of the conventional timepiece into that with 12H as a stepping cycle; 00:00 at midnight and 12:00 at noon being usually set as the stepping timings for the 12H stepping cycle; or alternatively, 6:00 am and 6:00 pm, or any other pairs that are 12 hours separated from each other may be selected as required.